This invention relates to telecommunications networks and, more particularly, to the convergence of voice telecommunications networks and packet data transport networks.
The public switched telephone network (PSTN) is in a state of evolution. The ever present demand for faster, more efficient transport of information across network resources, coupled with the desire for more advanced features and applications has sparked experimentation and innovation in the telecommunications industry.
One manifestation of the evolving public switched telephone network is the convergence of voice and data networks (hereinafter, xe2x80x9cconvergent networksxe2x80x9d) for providing telecommunications services. Traditionally, voice networks send information among nodes via well established signaling links and protocols. Packet-based data networks extend packets of digitized data over packet-based links using protocols completely different from circuit-based protocols. Packet-based data networks (such as the Internet) are traditionally utilized to interconnect computing systems. The telecommunications industry is realizing, however, that the convergence of circuit based and packet-based networks into a conglomerate produces a network with an immense capacity for voice and data transmission.
In traditional voice networks, features and applications including, but not limited to, announcement playback, automatic speech recognition and echo cancellation are provided by service circuits which have the hardware and software capability necessary for executing a variety of functions. Providing a function equivalent to the service circuit in a convergent network is challenging for it requires accommodation of both circuit-based and packet-based links and protocols.
It has been recognized that there is a need for providing service applications with a high degree of flexibility and equal efficiency to circuit-based and packet-based portions of a convergent telecommunications network. This need is addressed and a technological advance is achieved in the telecommunications art by a network resource server (NRS) element for providing many different classes of service circuit and server functions. The NRS can be initially connected to synchronous, circuit based facilities and, as a network migrates towards convergence, can transparently continue to provide service circuit type functions to both the packet-based and circuit based portions of the convergent network. Ultimately, in some embodiments the NRS will serve in only packet-based systems.
In one embodiment, the NRS is interconnected via circuit based transport links to at least one element (node) in a circuit-based network. The NRS is also interconnected via packet-based links to at least one node in a packet-based network. By maintaining interconnections to the circuit and packet portions of the convergent network, the NRS provides features and application functions to both portions of the convergent network.
More particularly, the NRS includes circuit based interfaces and packet-based interfaces managed by a controller interconnected to the interfaces via a high speed backplane. The high speed backplane is designed for both circuit and packet traffic. In one exemplary embodiment, the NRS also includes a plurality of digital signal processors, high powered reduced instruction set computing (RISC) processors and at least one custom processor for accommodating a variety of features and applications as may be required in the convergent network. The NRS also includes substantial random access memory (RAM) and a pointer processor contained within the RAM for providing multicast services to subscribers of the convergent network. A redundant array of an expensive disk is also included in the NRS to allow for bulk storage of memory intensive service functions such as announcements, movies on demand or web pages. In alternative embodiments, the NRS includes some subset of the above-mentioned components as appropriate for the needs of the network.
Advantageously, the NRS can replace all existing service circuit nodes within a traditional circuit based telecommunications system while maintaining sufficient capacity to serve all packet-based requests in a convergent or packet telecommunications system. The enhanced capacity of the NRS along with its flexible design and ability to provide a variety of features and applications results in cost savings and enhanced efficiency to service providers who choose to implement such an element in their convergent networks.